Method for demonstrating stain removal

Abstract

An in vitro method for demonstrating the stain removal efficacy of an oral care composition comprising (a) providing a substrate, (b) providing a staining solution, (c) providing a treatment solution comprising the oral care composition, (d) immersing the substrate in the staining solution, (e) removing the substrate from the staining solution, (f) evaluating the color of the stained substrate, (g) applying the treatment solution to the substrate and (h) evaluating the color of the treated substrate, wherein the staining solution comprises coffee is provided.

1 . An in vitro method for demonstrating the stain removal efficacy of an oral care composition comprising
 a. providing a substrate,   b. providing a staining solution,   c. providing a treatment solution comprising the oral care composition,   d. immersing the substrate in the staining solution,   e. removing the substrate from the staining solution,   f. evaluating the color of the stained substrate,   g. applying the treatment solution to the substrate and   h. evaluating the color of the treated substrate,   
       wherein the staining solution comprises coffee. 
     
     
         2 . The method according to  claim 1  wherein the staining solution comprises instant coffee powder. 
     
     
         3 . The method according to  claim 1  wherein the staining solution comprises instant coffee powder and an acid. 
     
     
         4 . The method according to  claim 1  wherein the staining solution comprises instant coffee powder at a concentration of from about 0.10 g/ml to about 0.60 g/ml. 
     
     
         5 . The method according to  claim 1  wherein the staining solution comprises instant coffee powder at a concentration of from about 0.20 g/ml to about 0.40 g/ml. 
     
     
         6 . The method according to  claim 1  wherein the staining solution comprises instant coffee powder at a concentration of about 0.25 g/ml. 
     
     
         7 . The method according to  claim 1  wherein the staining solution comprises acetic acid. 
     
     
         8 . The method according to  claim 1  wherein the staining solution comprises from about 0.5% to about 2.0% by volume glacial acetic acid. 
     
     
         9 . The method according to  claim 1  wherein the staining solution comprises about 1.25% by volume glacial acetic acid. 
     
     
         10 . The method according to  claim 1  wherein the staining solution comprises instant coffee powder at a concentration of about 0.25 g/ml and glacial acetic acid at a concentration of about 1.25% by volume. 
     
     
         11 . The method according to  claim 1  wherein the substrate comprises calcium carbonate. 
     
     
         12 . The method according to  claim 1  wherein the substrate comprises the exoskeleton of a marine bivalve mollusk. 
     
     
         13 . The method according to  claim 1  wherein the substrate comprises the exoskeleton of a marine bivalve mollusk in the family Arcidae. 
     
     
         14 . The method according to  claim 1  wherein the oral care composition is a dentifrice. 
     
     
         15 . The method according to  claim 1  wherein the oral care composition comprises silica and pyrophosphate. 
     
     
         16 . The method according to  claim 1  wherein the treatment solution comprises a slurry of an oral care composition and water. 
     
     
         17 . The method according to  claim 1  wherein the treatment solution comprises a slurry of dentifrice and water in a ratio of from about 1:2 to about 1:4 by weight. 
     
     
         18 . The method according to  claim 1  wherein the treatment solution comprises a slurry of dentifrice and water in a ratio of about 1:3 by weight. 
     
     
         19 . The method according to  claim 1  wherein step d comprises immersing the substrate in the staining solution for from about 20 to about 60 minutes. 
     
     
         20 . The method according to  claim 1  wherein step d comprises immersing the substrate in the staining solution for about 45 minutes. 
     
     
         21 . The method according to  claim 1  additionally comprising step e (ii) wherein the substrate is air-dried. 
     
     
         22 . The method according to  claim 1  wherein step g comprises immersing the substrate in the treatment solution for a period of from about 20 seconds to about 2 minutes. 
     
     
         23 . The method according to  claim 1  wherein step g comprises immersing the substrate in the treatment solution for a period of about 1 minute. 
     
     
         24 . The method according to  claim 22  wherein step g further comprises agitating the substrate in the treatment solution. 
     
     
         25 . The method according to  claim 1  wherein the treatment solution is applied to the substrate using a brush. 
     
     
         26 . The method according to  claim 1  wherein the color of the stained substrate and the color of the treated substrate is evaluated by measuring the L*a*b* values of the stained substrate and the treated substrate. 
     
     
         27 . A staining solution comprising instant coffee powder at a concentration of from about 0.10 g/ml to about 0.60 g/ml and from about 0.5% to about 2.0% by volume glacial acetic acid. 
     
     
         28 . The staining solution of  claim 27  comprising instant coffee powder at a concentration of from about 0.20 g/ml to about 0.40 g/ml and from about 0.5% to about 2.0% by volume glacial acetic acid. 
     
     
         29 . The staining solution of  claim 27  comprising instant coffee powder at a concentration of about 0.25 g/ml and about 1.25% by volume glacial acetic acid. 
     
     
         30 . (canceled)